(a) Technical Field of the Invention
The present invention generally relates to spray pumps, and more particularly to a pressure releasing device for quickly releasing the pressure in the hose of a spray pump to avoid dripping from the spray nozzle.
(b) Description of the Prior Art
A high-pressure spray pump is usually connected to a hose which has a spray nozzle at the other end. Water is pressurized by the pump, driven through the hose, and sprayed out via the nozzle. When the pump is turned off, the pressure of the water remaining in the hose cannot be released immediately and the high-pressure water would drip from the spray nozzle continuously until the pressure drops below a certain level, making the operation of the water spray system quite inconvenient. For some water spray systems, even though the pump is not turned on or is turned for a long time, dripping or leakage from the spray nozzle is still inevitable as the pressure of normal tap water is around 7 kg f/cm2. This pressure is not high enough to deliver sprays but, for these water spray systems, is still large enough to cause dripping from the spray nozzle. Conventionally, some sort of electromagnetic valve and timer are provided along the hose of the water spray system to prevent the foregoing problem. However, these additional devices imply a higher cost for the water spray system and increased difficulty in installing and operating the water spray system.